Building Internet Firewalls
- D. Brent Chapman, Elizabeth D. Zwicky - This is a solid, definitive text for building Internet firewalls that every system administrator who is connecting to the Net should own.

Building Linux and Openbsd Firewalls
- This book provides networking, Web, IT, and security professionals with simple, secure, and inexpensive techniques for building Linux and BSD firewalls.

Computer Security Basics
- Deborah Russell, G. T. Gangemi - O'Reilly & Assoc. (KEY) - The book describes complicated concepts such as trusted systems, encryption and mandatory access control in simple terms, and includes an introduction to the Orange Book.

Information Security Management Handbook, Fourth Edition
- Micki Krause (Editor), Harold F. Tipton - ompletely revised and updated, the new edition reveals the precise nuts and bolts of exactly how to secure systems against all intruders and security threats, no matter where they come from.

Linux Firewalls
- This book details security steps that a small non-enterprise business user might take to protect themselves when dealing with what the attacker may gain and what a victim may lose.

Linux Security Toolkit
- David A. Bandel - Drawing on his own extensive experience, Linux Journal columnist David A. Bandel explains the security problems common to all Linux distributions and shows you step-by-step how to fix them.

Practical Unix and Internet Security
- Simson Garfinkel, Gene Spafford - This second edition is a complete rewrite of the original book. It's packed with twice the pages and offers even more practical information for UNIX users and administrators.

Protecting Networks With Satan
- Martin Freiss - This book describes how to install and use SATAN and how to adapt it to local requirements and increase its knowledge of specific security vulnerabilities.

Solaris Security
- Peter H. Gregory - A technical guide for Solaris and UNIX system administrators, providing details of how to make a system secure whether its an organization-wide network or stand-alone workstation.

Stopping Spam
- Alan Schwartz, Simson Garfinkel - demonstrate technical, political, and social approaches to keeping spam out of your mailbox and off your system. They discuss the many ways spammers falsify their mail, using fraudulent techniques to disguise where they come from.